Shuttle



Nov. 28, 1939.

SHUTTLE 7 Filed March 15, 1938 T. MURPHY 2,181,667 M Patented Nov. 28, 1939 UNITED STATES eATENT OFFlCE 3 Claims.

This invention relates to automatically threading loom shuttles and is more particularly directed to thread tensioning devices therefor.

It has been heretofore proposed to associate I resilient thread tensioning devices with the threading eyes of automatically threading shuttles, but the devices heretofore proposed for this purpose have not performed satisfactorily in practice; brushes, felt pads and the like have therefore been more commonly employed to provide the necessary tension; It is found, however, that thetension cannot be maintained constant by such expedients and as the result of the uneven application of tension to the thread,

breakage commonly occurs as frequently as several times in an hour, with resultant interruption and delay in the operation of the machine.

It is an object of the present invention to overcome these difficulties and to provide a ten- 2 sioning device which will maintain substantially constant tension under varying operating conditions and with different grades of thread or yarn, and which will facilitate rather than impede the automatic feeding of the thread into the thread passage of the conventional shuttle eye, thereby minimizing thread breakage and materially reducing the amount of attention and supervision required for satisfactory operation of the loom.

0 It is a feature of the invention that when the thread is overloaded, for example in taking up the slack during the feeding in of a new thread, the device is capable of yielding so as to promptly reduce the tension, thereby automatically preventing thread breakage.

A further object of the invention is the provision of a thread tensioning device which is simple and inexpensive to construct, which will not cut or wear the thread, and which may be readily applied to conventional types of shuttle eyes without substantial modification thereof.

More specifically, the invention contemplates the provision, in a shuttle eye for loom shuttles, of a tensioning device including a spherical element and a cup-shaped seat therefor, the seat being yieldingly urged into engagement with the spherical element so that the thread may be guided therebetween and sufficiently retarded thereby to afford the desired degree of tension. The seat and the yielding means associated therewith are preferably disposed beneath the spherical element so that the feeding of the thread into the shuttle eye in the conventional manner is not interfered. Again, the thread, normally tending to move downwardly in the eye when (Ci. 139-2l7) excessive tension is applied thereto, may depress the seat against the action of the yielding means to momentarily relieve such excessive tension.

Further objects and features of the invention will be apparent from the following description taken in connection with the accompanying drawing, in which:

Figure 1 is a plan view of one end of a loom shuttle illustrating the application of the invention thereto; 19

Figures 2 and 3 are side and end elevations respectively of the shuttle eye shown in Figure 1;

Figure 4 is a longitudinal sectional View of the shuttle eye;

Figure 5 is a bottom plan View of the shuttle eye;

Figure 6 is a sectional View on an enlarged scale, taken substantially on the line 8-6 of Figure 4;' and 20 Figure '7 is an exploded view of the several cooperating elements of the tensioning device illustrated in the preceding figures.

In order to facilitate an understanding of the invention, reference is made herein to the em- 5 bodiment thereof illustrated in the accompanying drawing and specific language is used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, various further 30 modifications and alterations of the illustrated embodiment being contemplated such as would normally occur to one skilled in the art to which the invention relates. Y

In Figure 1 of the drawing is shown the forward end of a loom shuttle H3, it being understood that the shuttle is provided with conventional means for supporting therein a bobbin H. on which the thread It is wound. As the thread leaves the forward end of the bobbin, it is drawn i through a thread passage I3 extending longitudinally of the threading eye it, and thence passes about guide pins I! and is, mounted in the threading eye, emerging finally from the thread delivery opening l5 in the side of the shuttle. The threading block is provided with forwardly directed portions 20 and 2| and a downwardly directed horn 22 which are so shaped and positioned that on the first pick of the shuttle following replenishment, the thread is drawn downwardly between the projecting portions 2i! and 2! and past the horn 22 into engagement with the guide pins I1 and It, in which position it is shown in Figure 1. It will be observed that both the forward face of the horn 22 and 55 I intersect with the thread passage l3.

the pin I! are inclined downwardly and rearwardly so that the thread tends to move toward and remain in the bottom of the thread passage l3.

The structure thus far described is conventional and the details thereof form no part of the instant invention. It will, therefore, be appreciated that the elements of this structure are not claimed herein except to the extent that they enter into combination with the elements of the tensioning device and cooperate therewith to achieve the desired result. The application of the invention to other types of loom shuttles and threading eyes in the manner proposed herein is contemplated as a part of the present invention.

As shown more particularly in Figures 2, 4, and 6, a transverse opening 2G is formed in the shuttle eye M so as to extend th-erethrough and to As shown in Figure 2, the opening 26 is of generally rectangular shape as viewed in elevation, but is preferably rounded at its upper side. Received within the opening 26 is a seat 27 which is shaped so as to conform generally in elevation to the configuration of the opening, being of less depth than the opening, and so dimensioned as to slide freely in the latter in a vertical direction.

A generally parti-spherical recess 30 is formed in the upper side of the seat 27 to receive therein with a loose fit a spherical element 3|. A coil spring 33 engages the lower face of the seat 21 and is placed under compression by a set screw 34 threaded in an opening 35 in the lower portion of the threading eye, the screw 34 beingrecessed to receive and support the spring 33 and being provided in its outer end with a kerf 36, by means of which it can be readily turned to adjust the degree of compression of the spring. By the action of the spring 33, the seat 21--and the cooperating spherical element 3i are thrust upwardly, the latter being thereby seated at its upper side against the walls of the threading eye I4 which define the thread passage 13 at the upper side of the opening 26, the said walls being preferably slightly rounded at this point to definitely position and properly receive the spherical element 3!.

The mode of operation of the tensioning device will be apparent from the drawing and the foregoing description. Thus, during the threading operation, as the thread moves downwardly in the passage 13, it engages with and slightly depresses the spherical element 3 i, and moves about the same toward and into a position between the lower side of the spherical element and the bottom of the recess 39, in which position it is shown more particularly in Figures 4 and 6 of the drawing. The thread is now lightly clamped between the spherical element 3! and the seat 21 with a pressure determined by the adjustment of the screw 34, and constant tension is thereby applied to the thread as it is drawn off the bobbin ll, through the thread passage l3, and out at the thread delivery opening I5. During operation of the loom, the spherical element 3| fre quently rotates or shifts its position, and to this no doubt is attributable, at least in part, the smoothness of operation of the tensioning device. Again, if excessive tension or a sudden jerk is applied to the thread, for example on the first pick of the shuttle following replenishment, the seat 27 is permitted to yield downwardly against isting conventional types of shuttle eyes will be readily appreciated. Thus, the device need include only the four small elements shown in Figure 7 and may be incorporated in any ordinary form of automatically threading shuttle eye by no modification of the latter other than the formation therein of the transverse opening 26 and the threaded opening for the reception of the screw 34. It has been found possible to secure, by this slight modification of existing types of shuttle eye, a reduction of the frequency of thread breakage from an average of several times an hour to an average of once in seven or eight hours. 4

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In an automatically threading shuttle eye having a thread passage and means to direct a thread downwardly into said passage following replenishment, the combination with relatively displaceable cooperating thread engaging elements associated with said passage, of means located' beneath the lower of said elements for yieldingly urging the same upwardly and toward the other of said elements to frictionally grip the thread therebetween, the other of said elements comprising a freely floating spherical member.

2. In an automatically threading shuttle eye having a thread passage and means to direct a thread downwardly into said passage following replenishment, the combination with relatively displaceable cooperating thread engaging elements associated with said passage, of means located beneath the lower of said elements for yieldingly urging the same upwardly and toward the other of said elements to frictionally grip the thread therebetween, the upper of said elements being of spherical shape and the lower of said elements having a concave surface partially embracing said upper element.

3. In an automatically threading shuttle eye having a thread passage and means to direct a thread downwardly into said passage following replenishment, the combination with relatively displaceablev cooperating thread engaging elements associated with said passage, of means located beneath the lower of said elements for yieldingly urging the same upwardly and toward the other of said elements to frictionally grip the thread therebetween, the upper of said elements being of spherical shape and the lower of said elements having a concave surface partially embracing said upper element, said eye being so formed that the thread, when tensioned, extends away from said elements in a generally downward direction, whereby the lower of said elements may yield downwardly to relieve excessive tension on the thread.

' THOMAS MURPHY. 

